Can I manually lower the fan speed in a Cisco switch?

CardboardCardboard Member Posts: 43 ■■□□□□□□□□
Can the fan speed in a Cisco 3560 be manually lowered? I changed from Comcast to Verizon fios at my place recently. Speed test was showing 42 down / 6 up with Comcast. Once I got the fios, the tech said the speed was 150/150. I speed tested again and was getting 45 down / 38 up. Seems the Netgear WGT624 4 port switch in my room was a bottleneck. I plugged the modem directly into my pc and got 150 down / 160 up. I have some Cisco 3560s from my CCNA studies, and I plugged one of them in. I got speeds of 94 down / 98 up to several different cities. Not full speed, but way better than the Netgear 4 port could do. Only problem with the Cisco switch is the loud fans. I took it apart and started unplugging fans, but as soon as you unplug one, the rest go to full speed, which is louder. So I unplugged all 3 fans, and got a standard 80mm fan out of an old desktop pc I have. Cisco changes the wires around in the plug to try to make theirs unique and so you can only buy new fans from them, but I saw their game and defeated it. I moved the pins around in the 80mm fan plug to match and plugged it in. After experimenting, I reassembled the switch but left the side fan out so I could run the 80mm fan wires through the hole. Now the switch is under a desk, standing on end, with an 80mm fan taped in place, blowing air into the power supply. All is good, but still, it'd be nice if the fan wasn't running at 100%, it could be a little quieter. Is there any was to force the fan speed slower?


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    TechGromitTechGromit Member Posts: 2,156 ■■■■■■■■■□
    I worked with some equipment that allows you to control the speed of the fans, but I never seen a way to do it with Cisco switches. I believe the IOS controls the fan speed based on cooling needs, generally they are at the highest speed at POST and drop to a normal level after boot up. There no way I know to make them go slower than normal speed. Look at it from Cisco’s point of view, if you overheat (and damage) a switch by allowing you to turn down the fan speed, they are on the hook for warranty (and service contract) replacements. It also affects there equipment reliability ratings. There no benefit to them to allowing you fan speed control, switches are to be used in network closets, not sitting on someone desk or in someone living room, labbing.

    Still searching for the corner in a round room.
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